We find that adult GRK2+/− mice gain less weight after a long period (30 weeks) of HFD feeding building on our own data describing similar effects after a 12 weeks-long HFD-induced obesity [19, 20], and also when GRK2 was depleted in the middle of the HFD period [21]. The gene discussed is GRK2; the disease is obesity due to melanocortin 4 receptor deficiency.